President Trump's trade war with China is ratcheting up yet another notch: China says it will follow through with new and steeper tariffs on $60 billion worth of U.S. products to retaliate against U.S. tariffs that were unveiled Monday.

China's state-run news agency Xinhua said the retaliation would begin Sept. 24, the same day as the new U.S. tariffs on $200 billion worth of Chinese goods. China did not say which products from the U.S. that it will target, but the country did release a preliminary list on Aug. 3.

Trump threatened to hit back against China yet again if it follows through with the retaliation.

"If there's a retaliation against our farmers and our industrial workers, our ranchers, if any of that goes on, we're going to kick in another $257 billion," he said. "And that will be also at 25 percent. We don't want to do it, but we probably - we'll have no choice."